First i want to congratulate the 11bit team for a damn good job!
Now, to the point, i would suggest 2 more game modes:Story
Eg.: You start with a single character at night and first mission would be to escape the premises. After escaping you'll find an abandoned home and start from there, alone.
Next day mission would be to scavenge the home for supplies and eat (build a stove). After that you'll have to rescue your friend from some remote location, taken by bandits, but first you'll have a mission to build some weapon. Once rescued you now have a team of two.
Basically you will have to accomplish various missions, until the story walks you to BUILD, VISIT and USE all content from the game.Never ending warNo rescue is coming, how long can you survive ?